:root {
    --tsinghua-red: #a51e37;
    --tsinghua-dark: #333;
}

body {
    font-family: "Microsoft YaHei", sans-serif;
    margin: 0;
    color: #333;
    line-height: 1.6;
}

.container {
    width: 1200px;
    margin: 0 auto;
}

.tsinghua-header {
    background: white;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-top {
    border-bottom: 1px solid #eee;
    padding: 10px 0;
}

.logo {
    display: flex;
    align-items: center;
}

.logo img {
    height: 40px;
    margin-right: 15px;
}

.logo span {
    font-size: 22px;
    font-weight: bold;
    color: var(--tsinghua-red);
}

.header-links {
    float: right;
}

.header-links a {
    margin-left: 20px;
    color: var(--tsinghua-dark);
    text-decoration: none;
}

.main-nav {
    background: var(--tsinghua-red);
}

.main-nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
}

.main-nav li {
    position: relative;
}

.main-nav a {
    display: block;
    color: white;
    text-decoration: none;
    padding: 15px 20px;
    font-size: 16px;
}

.tsinghua-footer {
    background: var(--tsinghua-dark);
    color: white;
    padding: 30px 0;
    text-align: center;
    margin-top: 50px;
}

/* 轮播图样式 */
.banner {
    position: relative;
    height: 500px;
    overflow: hidden;
}

.slideshow {
    width: 100%;
    height: 100%;
}

.slide {
    position: absolute;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease;
}

.slide.active {
    opacity: 1;
}

.slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.slide-content {
    position: absolute;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    color: white;
    text-align: center;
    max-width: 800px;
    padding: 20px;
    background-color: rgba(0,0,0,0.6);
}

.slide-content h1 {
    font-size: 36px;
    margin-bottom: 15px;
}

/* 新闻区域 */
.section-title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin: 50px 0 20px;
    border-bottom: 2px solid var(--tsinghua-red);
    padding-bottom: 10px;
}

.section-title h2 {
    font-size: 24px;
    color: var(--tsinghua-red);
    margin: 0;
}

.more-link {
    color: var(--tsinghua-dark);
    text-decoration: none;
}

.news-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(400px, 1fr));
    gap: 30px;
}

.news-item {
    border-bottom: 1px solid #eee;
    padding-bottom: 20px;
}

.news-item h3 {
    margin: 0 0 10px;
}

.news-item h3 a {
    color: var(--tsinghua-dark);
    text-decoration: none;
}

.news-item h3 a:hover {
    color: var(--tsinghua-red);
}

.date {
    color: #999;
    font-size: 14px;
    margin-bottom: 10px;
}

/* 快速链接 */
.quick-links {
    background: #f5f5f5;
    padding: 50px 0;
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.link-card {
    background: white;
    padding: 30px;
    text-decoration: none;
    color: var(--tsinghua-dark);
    transition: transform 0.3s ease;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.link-card:hover {
    transform: translateY(-5px);
}

.link-card h3 {
    color: var(--tsinghua-red);
    margin-top: 0;
}

.qa-section {
    padding: 50px 0;
    background: #f9f9f9;
}

.qa-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

#qa-question {
    width: 70%;
    padding: 10px;
    margin-right: 10px;
}

#qa-response {
    margin: 20px 0;
    min-height: 100px;
    border: 1px solid #eee;
    padding: 15px;
    border-radius: 4px;
}

/* 关于我们页面样式 */
.about-section {
    padding: 50px 0;
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-image {
    margin: 30px 0;
    text-align: center;
}

.about-image img {
    max-width: 100%;
    height: auto;
    border-radius: 4px;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin: 40px 0;
}

.stat-item {
    text-align: center;
    padding: 20px;
    background: #f5f5f5;
    border-radius: 4px;
}

.stat-item h3 {
    color: var(--tsinghua-red);
    font-size: 36px;
    margin: 0 0 10px;
}

.main-nav a.active {
    background: rgba(255,255,255,0.2);
}